Q From Gary Beech: Can you please tell where eavesdrop and eavesdropper originate?
A It began in Anglo-Saxon England. The word came from Old Norse and originally referred to the area around a building that was liable to be wetted by water flowing off the projecting eaves of the roof above (gutters hadn’t been invented yet). There was an ancient custom that stopped a landowner from building within two feet of his boundary, for fear that the water cascading off the eaves might cause problems for his neighbour.
By the end of the medieval period, the word eavesdropper had been invented for somebody who stood within this strip of ground, under the projecting eaves and close to the walls of a building, in order to listen surreptitiously to the conversations within. The verb to eavesdrop in the same sense came along about a century later.